1. Field of the Invention
The present invention relates to the field of optical recording media and more particularly, to a disc in which a digital versatile disc (DVD) application is recorded on a physical layer of a compact disc (CD) and a recording/reproducing apparatus and method thereof.
2. Description of the Related Art
A DVD video format is used to record and reproduce high image quality video data and/or high sound quality audio data having a transmission rate of about 10 Mbps (mega bits per second). However, a DVD is generally used by people who do large-scale marketing, such as film producers, since it is very expensive to manufacture DVDs.
At present, popular CDs have become much cheaper and even common users can directly manufacture CDs with the spread of the CD-R (Recordable). Also, 32×-speed CD drives are now on the market due to the development of new techniques for CD drives.
Given that the transmission rate of CDs is about 1.5 Mbps, 8×-speed or greater CD drives have a 10 Mbps or faster transmission rate. Therefore, data recording and reproduction at the same rate as the transmission rate of DVDs is possible. However, the recording time of CDs is much shorter than that of DVDs. Therefore, CDs cannot record data for a long period of time. However, CDs can be used when high image quality reproduction is required for a short time for applications such as clips for presentations or promotions.
However, since existing CD recorders cannot record this high image quality DVD data, new recorders are required. Even if DVD data can be recorded on a CD, existing CD/DVD players will recognize a disc on which DVD data is recorded as a CD and play the disc using a playing process for CDs. Thus, reproduction of the DVD data recorded on the CD is not possible since the disc is a CD in terms of its physical properties but is a DVD in terms of its logical structure.
In FIG. 1, which is a flowchart for illustrating a reproducing method performed by a conventional CD player, a focusing servo is controlled so that the information on the disc loaded into the CD player is properly picked up and, thus, the information in a lead-in area of the disc is read in step S101.
General CDs include audio CDs, video CDs, and CD-ROMs. A CD-ROM is a disc (q; having a logical format which is used for data recording with a computer in contrast to an audio CD or a video CD. These CDs are differentiated by the control information in a sub-Q area of the lead-in area and Stable of contents (TOC) information. If an audio CD is prescribed in the control information in the sub-Q area, the CD is immediately recognized as an audio CD. If general data other than the audio CD is prescribed in the control information on the sub-Q area, the CD is recognized as a video CD or a CD-ROM.
That is, the control information of the sub-Q area in the lead-in area is analyzed in step S102. A determination as to whether an audio CD is prescribed in the control information of the sub-Q area is made using the above analysis in step S103. If it is determined in step S103 that an audio CD is prescribed in the control information of the sub-Q area, audio data is reproduced by an audio CD playing process in step S104. If it is determined in step S103 that an audio CD is not prescribed in the control information of the sub-Q area, TOC information is analyzed in step S105.
Then, it is determined whether a video CD is prescribed in the analyzed TOC information in step S106. If it is determined in step S106 that a video CD is prescribed in the analyzed TOC information, the video CD information recorded on the first track of the disc is read in step S107 and, then, video data is reproduced by a video CD playing process according to the read first track information in step S108. If it is determined in step S106 that a video CD is not prescribed in the analyzed TOC information, the disc is recognized as a CD-ROM and, then, the fact that it is impossible for the CD player to play the loaded disc is displayed in step S109. Then, the playing process is ended.
In existing CD players for recognizing and playing only audio CDs and video CDs, and in existing CD/DVD players for recognizing and playing audio CDs, video CDs, and DVDs, a disc proposed by the present invention, on which DVD format data is recorded on a physical layer of a CD-type disc, is recognized as a CD and a general CD reproducing process is performed. Therefore, reproduction of the DVD format data is not possible.